Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752752AbWLSGfk (ORCPT ); Tue, 19 Dec 2006 01:35:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752661AbWLSGfk (ORCPT ); Tue, 19 Dec 2006 01:35:40 -0500 Received: from smtp.osdl.org ([65.172.181.25]:57882 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752672AbWLSGfi (ORCPT ); Tue, 19 Dec 2006 01:35:38 -0500 Date: Mon, 18 Dec 2006 22:34:14 -0800 (PST) From: Linus Torvalds To: Nick Piggin cc: Peter Zijlstra , Andrew Morton , andrei.popa@i-neo.ro, Linux Kernel Mailing List , Hugh Dickins , Florian Weimer , Marc Haber , Martin Michlmayr Subject: Re: 2.6.19 file content corruption on ext3 In-Reply-To: <45876C65.7010301@yahoo.com.au> Message-ID: References: <1166314399.7018.6.camel@localhost> <20061217040620.91dac272.akpm@osdl.org> <1166362772.8593.2.camel@localhost> <20061217154026.219b294f.akpm@osdl.org> <1166460945.10372.84.camel@twins> <45876C65.7010301@yahoo.com.au> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1030 Lines: 35 On Tue, 19 Dec 2006, Nick Piggin wrote: > > We never want to drop dirty data! (ignoring the truncate case, which is > handled privately by truncate anyway) Bzzt. SURE we do. We absolutely do want to drop dirty data in the writeout path. How do you think dirty data ever _becomes_ clean data? In other words, yes, we _do_ want to test-and-clear all the pgtable bits _and_ the PG_dirty bit. We want to do it for: - writeout - truncate - possibly a "drop" event (which could be a case for a journal entry that becomes stale due to being replaced or something - kind of "truncate" on metadata) because both of those events _literally_ turn dirty state into clean state. In no other circumstance do we ever want to clear a dirty bit, as far as I can tell. Linus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/